Tony Paley:Tony McCoy has elected to ride the Ted Walsh-trained Colbert Station in Saturday's Grand National at Aintree with bookmakers cutting the horse into a best-priced 11-1 on the news which was revealed as the final declarations for the race were made on Thursday morning.

The champion jockey had a difficult choice as his other JP McManus-owned option was the Jonjo O'Neill's Sunnyhillboy, beaten by the narrowest margin possible in the big race 12 months ago by Neptune Collonges.

McCoy told the Telegraph: "It's been very hard but after to speaking to JP McManus, who owns both of them, this morning we've decided I'll ride Colbert Station. I can't ride both of them and while he does not have the Aintree experience of Sunnyhillboy he looks less exposed to the handicapper and has a proper racing weight."

Walsh also runs Seabass, third last year and once again partnered by his daughter, Katie. Sunnyhillboy will again be ridden by Richie McLernon.

Imperial Commander is at the head of the weights after the good ground at Aintree persuaded his connections to let him take his chance and his trainer, Nigel Twiston-Davies, also has two more horses in the field in Major Malarkey, ridden by Tom Scudamore, and Viking Blond [Adam Wedge], who is the final horse of the 40 declared runners.

The ante-post favourite is the Willie Mullins-trained On His Own, ridden by Ruby Walsh. Mullins also runs Quel Esprit and Quiscover Fontaine.

Champion trainer Paul Nicholls, who claimed his first National last season in such thrilling circumstances, has Join Together [Daryl Jacob], What A Friend [Sam Thomas] and Harry The Viking [Ryan Mahon]. What A Friend and Harry The Viking are part-owned by Manchester United manager Sir Alex Ferguson.

Donald McCain runs 2011 winner Ballabriggs, Weird Al and Across The Bay, while Nicky Henderson, still searching for his first win in the race, is represented by Roberto Goldback.

Chicago Grey and Tarquinius run for another former successful trainer in Gordon Elliott. Elliott was set to have a third runner in Backstage, but he scoped on Thursday morning.

Cappa Bleu, fourth last year, is aiming to maintain Evan Williams' great recent record of having had a placed runner for the last four years.

Oscar Time, second two years ago, is back again and will be ridden by Sam Waley-Cohen.

Quinz, Poker De Sivola, Cloudy Lane and Pearlysteps have also been taken out in and Mortimers Cross and Pentiffic are the two reserves.

Thursday's best bets, by Greg Wood

You can read my thoughts on the first five races at Aintree on Channel 4 on today's card here. In the Manifesto Novice Chase, Fago (4.50) comes here fresh having skipped the Cheltenham Festival and is expected to bounce back from a disappointing run at Sandown while Jetson (5.25), who stayed on well to finish third in the Pertemps Hurdle at the Festival, has the added advantage of Tony McCoy on board in the Silver Cross Handicap Hurdle.

Stan James Grand National Tipping competition, day three

Chris1623 leads the field over the water jump and past the stands at the end of the first circuit, having added Lightening Rod (6-1) to his winner on day one. SmokingGun1, slackdad38 and no1octoberfest paired Galway Jack (85-40) with Twenty One Choice (5-1). Lindsey6677 and pd13 had Galway Jack and Lightening Rod.

This week's prize is a £50 bet on Saturday's Grand National, generously offered by Stan James. We'll contact you on Friday evening if you win, to arrange the bet for the next day.

By the way, can anyone help Beeftodd with his musings? He wondered yesterday whether a racehorse had "ever been named after a musical act or vice versa". Off the top of my head, I think the band Franz Ferdinand chose the name because one of them had a winning bet on Archduke Ferdinand in the Pitmen's Derby. There must be others?

As ever, our champion will be the tipster who returns the best profit to notional level stakes of £1 at starting price on our nominated races, of which there will be four each day up until Friday. Non-runners count as losers. If you have not joined in so far this week, you are welcome to do so today, but you will start on -6.

In the event of a tie at the end of the week, the winner will be the tipster who, from among those tied on the highest score, posted their tips earliest on the final day.